Bio-based cyanophycin packaging materials platform for sustainable plastics

Overview

Conventional plastics rely on non-renewable fossil fuel feedstocks and contribute significantly to greenhouse gas emissions, while global recycling rates remain low. Existing bioplastics offer sustainability advantages but are limited by a lack of functional diversity and tunability, making it difficult to engineer their properties for diverse applications. This project addresses these limitations by developing an integrated computational design and biosynthesis workflow for creating novel, 'new-to-nature' bio-based materials with tailored properties.

The focus is on cyanophycin, a natural biopolymer composed of an L-aspartic acid backbone with L-arginine side-chains. Cyanophycin is biosynthesized by a single enzyme, cyanophycin synthetase (CphA1), which is robustly active in heterologous (non-native) host systems such as Escherichia coli. This single-enzyme synthesis pathway streamlines protein engineering efforts and enables a wide variety of potential chemical modifications. The ultimate goal is to demonstrate miscibility with conventional polymers like PET and PE, validate environmental sustainability of resulting blends, and ultimately eliminate the use of fossil-fuel-based plastics in packaging.

Technical specifications

Core technology:

• Cyanophycin biopolymer produced via the CphA1 enzyme in engineered microbial hosts
• Integrated computational design workflow to model key material properties across large polymer variant libraries
• Single-enzyme biosynthesis that simplifies protein engineering and enables rapid iteration of polymer variants

Key features:

• Tunable mechanical and functional properties through targeted modifications to the cyanophycin backbone and side-chains
• Compatibility with conventional polymers such as PET and PE, enabling composite blends with improved sustainability and mechanics
• Validated using analytical chemistry, X-ray synchrotron methods for crystallinity analysis, and in situ mechanical testing
• Composite mixtures with other polymers demonstrate far improved sustainability and mechanical performance compared to polymers alone

Technology readiness level

The technology has progressed beyond initial concept validation. Researchers have used analytical chemistry and X-ray synchrotron methods to examine crystallinity, alongside in situ mechanical testing, to demonstrate the mechanical capabilities of cyanophycin-based materials. Composite mixtures with other polymers have already shown improved sustainability and mechanical properties. Future validation efforts will focus on demonstrating miscibility with PET and PE, proving environmental sustainability of the blends, and working toward the elimination of conventional fossil-fuel-based plastics in packaging. The platform is positioned for further development of new cyanophycin variants and expansion into additional bio-based material applications.